Arrangement for anaesthetising a living creature

ABSTRACT

The invention relates to an arrangement ( 200 ) for anaesthetising a living creature (V) and for maintaining said creature in an anaesthetised state, by administering thereto an infused volume of anaesthesia inducing pharmaceutical ( 22 ) in liquid phase per unit of time, with the aid of one or more lung ventilator units (A) and one or more infusion units (B). Chosen parts of the lung ventilator unit, with the exception of external insufflation hose, expiration valve, measuring probe and a number of hoses ( 12 ), and selected parts of the infusion unit (B), with the exception of cannula ( 5 B) and hose ( 4 B) are mutually combined to form a single equipment unit ( 201 ). Some of the parts of the equipment unit are mutually coordinated with respect to communication via a computer unit ( 600 ) included in the equipment unit, and the computer unit is adapted to monitor unit related criteria and creature related criteria.

This is a U.S. National Phase Application Under 35 USC 371 and applicantherewith claims the benefit of priority of PCT/SE00/00910 filed May 8,2000, which was published Under PCT Article 21(2) in English andApplication No. 9901688-3 filed in Sweden on May 10, 1999.

FIELD OF INVENTION

The present invention relates to an arrangement for initiallyanaesthetising a living creature and to keep the creature within adaptedlevels of said anaesthetic state, the so-called depth of anaesthesia.

Such states and depths of anaesthesia are achieved by infusing orinjecting into a living creature a volume of anaesthesia inducingpharmaceutical in a liquid phase per unit of time.

By “infused” is meant the continuous or intermittent and/or controllabledelivery of said pharmaceutical (anaesthetic) to a blood-carryingvessel, preferably intravenously.

During this state there is required, among other things, the use of alung ventilator and associated control unit, and an infusion unit andassociated control unit, to regulate the increase in or reduction in thevolume of pharmaceutical per unit of time required to regulate the depthof anaesthesia.

In addition, arrangements of this kind comprise and/or include aplurality of sensors and/or measuring probes adapted to sense selectedcreature-associated criteria and to produce a signal that corresponds tothe chosen criterion and its value or intensity at that moment in time.

Examples of criteria thus selected and their intensity will be mentionedin the following text.

The invention can be applied to any living creature that has a lungfunction and will be illustrated in the following with reference to itsapplication on a human being, represented by a patient undergoingsurgery, by way of simplification.

DESCRIPTION OF THE BACKGROUND ART

With respect to earlier known apparatus and arrangements foranaesthetising a patient to a chosen depth of anaesthesia, it is normalto divide such states into three different categories, depending on thedegree of consciousness of the patient, namely:

-   -   general anaesthesia, a state in which the patient is rendered        unconscious artificially and kept within adapted degrees or        levels of unconsciousness (depth of anaesthesia);    -   regional anaesthesia, a state of insensitivity in the spine of a        patient; and    -   local anaesthesia a state which is mainly applicable to minor        surgery or treatment.        The patients are conscious in the latter two categories.

The present invention is adapted for application in the generalanaesthesia category.

This category includes two different groups of anaesthesia, namelyinhalation anaesthesia and total intravenous anaesthesia.

There is used within the first anaesthesia group, inhalationanaesthesia, a lung ventilator that includes vaporiser equipment foranaesthesia inducing pharmaceutical, said lung ventilator creatingconditions for the insufflation and expiration of air or air mixed withgaseous oxygen, which is mixed, in turn with anaesthesia inducing gases.

Although apparatus designed for inhalation anaesthesia have found wideuse, they require the appropriation of very complicated equipment,partly to enable the insufflation and expiration phases to be controlledand partly to administer the supply of gaseous pharmaceutical, and alsoto evaluate patient related criteria and to regulate said criteria whennecessary.

Thus, it is likely that anaesthesia inducing gases will accompany theexpiration gas in each expiration phase and consequently it is necessaryto remove these gases from every enclosed space, such as the operatingtheatre, effectively and at short intervals. In addition, the equipmentmust, of course, be gas tight in general.

It is also known in the case of such practice to assemble an inhalationanaesthesia related system within respective clinics with the aid ofdifferent apparatus obtained from different manufacturers and designedfor different purposes.

It is also known to appropriate a single system from a singlemanufacturer. Such systems, however, are highly complicated and thecomponent parts of such systems make the equipment extremely heavy. Itis also found that such a system is space consuming and expensive andthat the necessary inspections for possible leakage are very difficultto carry out.

The present invention relates to and includes an arrangement within thesecond anaesthesia group, i.e. total intravenous anaesthesia, wherein avolume of occurring or existing anaesthesia-inducing pharmaceutical inliquid phase is allowed to infuse per unit of time into the bloodstreamof the living creature or patient.

It is necessary in this case to use a lung ventilator and an infusionunit which, with the aid of a control unit, is able to induce a givendepth of anaesthesia in the patient and to keep the patient withinadapted levels of said chosen depth of anaesthesia.

It is known in this respect to use a number of apparatus taken fromdifferent manufacturers and to assemble these apparatus into a system oran arrangement. In order to induce a given depth of anaesthesia in apatient, each such system requires the use of a number of apparatus andmeasuring devices which function to enable a number of important patientcriteria to be evaluated and to enable the well-being of the patient tobe controlled. These criteria have normally been presented asinstantaneous values and/or curves on the display surface of eachapparatus.

Criteria that concern the well-keeping/treatment of a patient aredesignated therapeutic criteria and are detected/sensed, regulated andevaluated in one or more therapeutic units.

Criteria that relate to patient diagnosis or patient supervision arereferred to as diagnostic criteria and are sensed/detected and evaluatedin one or more diagnostic units.

Some significant units and criteria in the present context have beenlisted in FIG. 1, in which reference sign A identifies a lung ventilatorand an associated control unit; B identifies an infusion unit andassociated control unit for making necessary adjustments to the volumeof anaesthesia inducing pharmaceutical per unit of time; C identifies aunit which senses/detects prevailing air pressure, i.e. the air pressurein the mouth of the patient; D identifies a unit which evaluates theflow of air into the patient's lungs and, when necessary, also out ofthe lungs; E identifies a unit which evaluates the CO₂-content and theO₂-content of the air entering the lungs, and when necessary also theexpiration air; F identifies a unit for evaluating ECG-values; Gidentifies a unit that evaluates blood pressure values NIBP; Hidentifies a unit for establishing oxygen saturation in the blood(SpO₂); I identifies a unit which evaluates the degree of consciousnessof the patient (the depth of anaesthesia) via sensed brain activity (theBIS-values); and J identifies a unit which evaluates PEEP-value.

It is known in systems of this nature adapted for total intravenousanaesthesia to allow a number of the criteria given under A–J above tobe interconnected and combined in a common unit.

For instance, it is known to combine the units for criteria C and J andfor A, D and E respectively into a single unit. The criterion B andcombinations of criteria F, G and H normally require separately operatedand individual units.

Known technology teaches the use of the infusion unit B and the lungventilator A as separate units. These units are used to control thewell-being of the patient and therefore include a number of therapeuticunits.

Other equipment and units are primarily designed to produceinstantaneous values or curves for other relevant patient-relatedcriteria and include a number of diagnostic units.

By instantaneous values shall be understood measured values that can beevaluated instantaneously in the true meaning of the word, and also theformation of mean values of a selected number of sensed/detectedinstantaneous measurement values.

In the case of so-called multi-parameter monitors, it is known toco-ordinate the evaluated instantaneous values and the values forpresentation of time-related graphs for selected relevant criteria andto show these graphs on a display surface.

SUMMARY OF THE PRESENT INVENTION

Technical Problems

When taking into consideration the technical deliberations that a personskilled in this particular art must make in order to provide a solutionto one or more technical problems that he/she encounters, it will beseen that on the one hand it is necessary to realise the measures and/orthe sequence of measures that must be undertaken to this end, and on theother to realise which means is/are required in solving one or more ofsaid problems. On this basis, it will be evident that the technicalproblems listed below are highly relevant to the development of thepresent invention.

When considering the present standpoint of techniques as describedabove, it will be seen that a technical problem is one of providing withsimple means an arrangement which enables the infusion of anaesthesiainducing pharmaceutical and which is based on principles for totalintravenous anaesthesia while using one or more lung ventilator unitsand one or more infusion units, with first means for monitoringunit-related criteria, and second means for monitoring patient-relatedcriteria, therewith creating conditions for a compact and mobilearrangement.

In this respect, a technical problem resides in realising thesignificance of and the advantages afforded by allowing the componentparts of the chosen lung ventilator, with the exception of insufflationhose, expiration valve, measuring probe and a number of hoses, and thecomponent parts of the infusion unit, with the exception of cannula andhose, to be combined into a single equipment unit, and to mutuallyco-ordinate certain of said equipment unit parts from the aspect ofcommunication through the medium of a computer unit arranged in theequipment unit, and to program the computer unit to monitor patientrelated criteria and unit related criteria.

In addition, a technical problem resides in realising the significanceof and the advantages that are associated with programming the computerunit to distinguish between therapeutic criteria and diagnostic criteriathrough the medium of therapeutic units and diagnostic units includedand mounted in said equipment unit.

Another technical problem resides in realising the significance of andadvantages afforded by structuring one or more therapeutic unit and/orone or more diagnostic units on a printed circuit board or card and,when applicable, function units mounted on or related to said circuitboard, and coordinating several such boards in the equipment unit,wherewith an input of respective units is coupled internally in theequipment unit to one part of a two-part coupling means, where saidparts are fastened to and co-ordinate in said equipment unit, and torealise that said parts of the coupling means belonging to saidequipment unit shall be comprised of one or more hose couplings and oneor more couplings/connections for electric conductors or cables.

It will also be seen that a technical problem resides in the provisionof conditions with the aid of simple measures that enable an externalinsufflation-hose section for the lung ventilator unit and its couplingpart associated with said equipment unit to be co-ordinated with furtherexternal hose parts so as to enable an external hose bundle or assemblyto be used, said hose bundle conveniently including a hose forcontrolling a patient-proximal expiration valve, two hose parts formeasuring pressure differences, a hose part for measuring pressureand/or a gas sampling hose part.

In addition, a technical problem resides in providing with the aid ofsimple measures conditions which allow the infusion unit to include acontainer that is held detachably by the equipment unit and thatcontains an anaesthesia inducing pharmaceutical in liquid phase.

Another technical problem is one of creating with the aid of simplemeasures conditions which enable the coupling parts associated with theequipment unit to be connected to a measuring probe, sensor or likedevice peripherally situated and separated from the equipment unit,through the medium of a hose part or an electric conductor, where saidmeasuring probe, sensor or like device may include electronic circuitsthat are designed to sense the occurrence of patient related criteriaand to establish the values of said criteria.

It will also be seen that a technical problem resides in providing withthe aid of simple measures conditions that will enable such an equipmentunit to be coupled to and/or readily releasably connected to a displayunit adapted to display on a display surface one or more of theinstantaneous values of criteria and/or timewise variation of saidcriterion.

In this respect, a technical problem resides in realising thesignificance of and the advantages that are afforded by presentingrequisite diagnostic criteria and requisite therapeutic criteria in aco-ordinated fashion, thereby greatly assisting the anaesthetist and thesurgeon in controlling and regulating the therapeutic criteria and/ordiagnostic criteria of the patient, such as the depth of anaesthesiaand/or other changeable states.

Another technical problem is one of creating with the aid of simplemeans or measures conditions which enable the timewise variation of anumber of chosen criteria to be presented on an image screen or displaysurface with at least some chosen time axes coordinated, for instancesuperimposed with respect to each other, and, when necessary,compensating for any lag time in evaluating the measuring result.

Another technical problem is one of providing with the aid of simplemeasures conditions that allow the timewise variation of one or more,although only a few, chosen criteria to be presented on an image screenor display surface in a time-axes time scale that is different to thetime axes for other criteria.

Another technical problem is one of realising the co-ordination that isrequired to allow the predominant part of requisite circuits, units andequipment to be combined into a single equipment unit, where requisitemeasuring points, measuring probes, sensors, etc. can be connected tosaid equipment unit via coupling means in an easy and functionallyreliable fashion.

Another technical problem resides in providing an arrangement capable ofreadily effecting in the equipment unit such requisite processes as gassampling/measuring, flow measuring, volume measuring, pressuremeasuring, ECG-measuring, saturation measuring and/or measuring thedepth of anaesthesia.

Yet another technical problem is one of providing an arrangement of thekind described in the introduction in which the equipment unit used isadapted to include the major part of a lung ventilator and itsassociated control unit, and to couple said ventilator to a computerunit.

It will also be seen that a technical problem is one of realising thesignificance of providing an arrangement in which the entire lungventilator is incorporated in the equipment unit, with the exception ofa hose portion that conducts insufflation gas to the patient, an outerportion of said hose for connection to an expiration valve, one or morehose portions extending between said valve and said unit, a hose portionfor actuation of the expiration valve to one of two positions from theequipment unit, a hose portion for determining gas pressure values andan adapted lowest overpressure value, and two hose portions belonging tothe measuring probe for transferring flow-dependent gas pressure valuesto the equipment unit, said values being used to measure flow, and alsosaid measuring probe and a hose portion for gas analysis.

It will also be seen that a technical problem resides in creatingconditions which enable all important function units to be combined inone single equipment unit, so that said unit can be attached to areadily accessible first part of a two-part hose coupling, said couplingpart being adapted for coaction with a number of further hoses inaddition to coaction with an outer hose part for insufflation gas.

It will also be seen that in respect of an arrangement of the kinddescribed in the introduction a technical problem resides in enablingreadily available first coupling parts of one or more two-part hosecouplings to be connected to the equipment unit, where said firstcoupling parts are adapted for coaction with one or more hoses forevaluating different selected criteria, such as CO₂-content, O₂-content,breathing frequency and like alternatives for pressure actuation of anexpiration valve.

Similarly, it will be seen in respect of an arrangement of the kinddescribed in the introduction that a technical problem resides inenabling one or more first coupling parts of one or more readilyaccessible two-part electric coupling parts to be attached to saidequipment unit, where said first coupling parts are adapted for coactionwith one or more external electric cables which carry electric signalsrepresentative of different chosen criteria, such as the timewisepresentation of ECG-values, PLET-values and BIS-values, andinstantaneous values of the same or different chosen criteria, such asthe HR-value, S_(p)O₂-value and BIS-value respectively.

Another technical problem resides in enabling the use of a display unitthat is designed for inclusion in an arrangement and which co-acts withan equipment unit for presenting thereon timewise variations of themeasurement values applicable to chosen criteria and the instantaneousvalues of the same or other chosen criteria, and structure these valueson said display surface so that they can be readily discerned and read,said display surface presenting one or more patient related criteriaduring a chosen depth of anaesthesia caused by said patient infusing avolume of anaesthesia inducing pharmaceutical per unit of time.

It will also be seen that a technical problem resides in enabling themeasurement values and data obtained from chosen patient relatedcriteria to be distributed so that said values and data can be readeasily on the display surface and readily modified, for instance throughthe medium of display-surface related fields and the orientation of saidfields and/or through the medium of button or knob actuation.

Another technical problem is one of realising the significance ofallowing a first wide surface area of the display surface to be adaptedto show the timewise variation of a number of criteria, and a secondsmaller surface area adapted to show the instantaneous values, thehighest and lowest values etc. of a number of criteria.

It will also be seen that a technical problem is one of realising thesignificance of and the advantages afforded by allowing the firstsurface area to be adapted to show the timewise variation of a number ofcriteria, by orientating a chosen number of said criteria with the timeaxes being mutually equal and in superimposed relationship.

A further technical problem is one of realising the significance of andthe advantages afforded by allowing a second surface area to be dividedinto fields such that relevant criteria can be displayed in each field,for instance in an abbreviated form, and to display adjacent thereto theinstantaneous value of the criteria and the alternative maximum andminimum values or calculated values thereof.

In respect of an arrangement of the kind described in the introductionand comprising an equipment unit and a display unit, still anothertechnical problem is one of realising the advantages that are affordedwhen said display unit is rotatably mounted on and easily detached fromthe front part of the equipment unit, such as above a container thatencloses anaesthesia inducing pharmaceutical and that can be actuated bythe control unit of an infusion unit, and also to realise thesignificance of such placement.

It will also be seen that a technical problem is one of creating withthe aid of simple measures conditions that enable a control circuit inthe control unit for regulating the volume of anaesthesia inducingpharmaceutical supplied by unit of time to be actuated through themedium of actuating means positioned adjacent to and preferably abovesaid container.

Another technical problem is one of realising the significance of andthe advantages afforded by allowing one or more control circuits in saidcontrol unit in the control unit for regulating criteria related to thelung ventilator to be actuated through the medium of actuating meanslocated adjacent to and on one side of said container.

Another technical problem is one of realising the significance of andthe advantages afforded by allowing one or more control circuits forcontrolled regulation of other criteria to be actuated through themedium of actuating means positioned in one or more rows within a thirdsurface area of a display surface.

Another technical problem resides in creating conditions for providingwithin the limited volume of the equipment unit activatable regulatingdevices that are adapted to hold a chosen value of a chosen criterionconstant for regulating purposes.

In addition to these problems it will be seen that a further technicalproblem resides in creating with the aid of simple measures anarrangement for total intravenous anaesthesia, where said arrangementcan be managed much more simply than earlier known combined andco-ordinated arrangement set-ups and which is designed to fulfilrequirements laid down by the authorities, which results in reducedmaintenance costs, which is more reliable in operation, and whichsatisfies the desire for less or small bulk, and which is therewithmobile.

Another technical problem is one of realising the significance of andthe advantages afforded by enabling the expiration gas of the patient tobe conducted out into the room while the patient is anaesthetised,therewith facilitating cleaning of the ventilator and reducing the wearand tear thereon, while utilising a much smaller compressible volume(less than half).

The use of a display unit enables different magnitudes to be combined onthe display surface and to phase shift and time-adapt the magnitudes,such as a pressure curve against a sample CO₂-curve.

It is also possible to plot one magnitude against another, for instancein an XY-diagram (PQ-loops and PV-loops).

It is also possible to establish co-variations, for instance changes inblood pressure or BIS in respect of a changed infusion rate, via aTREND-function.

A further technical problem resides in the creation of conditions withthe aid of simple measures and with the use of a computer unit whichenable advanced calculations or computations to be carried out bycollecting together all parameters, for instance lung mechanics andindirect calorimetry and other associated advanced expert systems, wherethe computer is able to monitor a plurality of parameters and to drawlogical conclusions therefrom, for instance give an early indication ofproblems and/or initiate the need for advice, for instance in reducinglung compliance (the stretchability of the lung).

Another technical problem resides in creating with the aid of simplemeasures and with the use of a computer unit conditions that makepossible a closed-loop anaesthesia process, e.g. enable the infusionrate from which the BIS-values are obtained to be controlled, or tocontrol the lung ventilator on the basis of the CO₂-values obtained.

Another technical problem is one of creating with the aid of simplemeasures and with the use of a computer unit conditions for reducingand/or totally eliminating mischievous alarms (several alarms resultingfrom the same basic cause) and to make possible so-called smart alarms,wherewith the computer unit initially sets the alarm limits on the basisof obtained patient criteria, therewith making things easier for theuser.

Another technical problem is one of creating with the aid of simplemeasures and with the use of a computer unit conditions which enable adisplay image or display surface to be transmitted to another localityvia telecommunications, e.g. via the Internet.

This enables the display surface to be presented on-line forconsultation with another doctor in another district and locality.

The invention also provides the option of presenting display images ofdiffering advanced degrees and therewith adapt the system to the needsand experience of the user.

The interface can also be readily updated for different languages and/orto provide technical services and updating of software in the systemover the telecommunications network.

A technical problem resides in creating with the aid of simple measuresand with the use of a PC-compatible computer unit conditions foradvanced statistic data processing, and economic follow-up of the use ofthe machine and the consumption of pharmaceuticals for instance, andenables the use of standard PC-components, for instance card readers,for entering patient journals, and to utilise readily the speed andinexpensive development of PC-technology in other respects.

A further technical problem is one of creating with the aid of simplemeasures and with the use of a computer unit conditions for plotting theinfusion characteristic of the infusion unit on the display surface andalso to allow the user to insert the value mg/kg/h instead of ml/h.

Solution

The present invention thus takes at its starting point an arrangementfor anaesthetising a living creature by administering thereto an infusedvolume of an anaesthesia inducing pharmaceutical in liquid phase perunit of time, while using one or more lung ventilator units and one ormore infusion units, and by using first means to monitor unit-relatedcriteria and second means to monitor patient related criteria.

With the intention of solving one or more of the aforesaid technicalproblems it is proposed in accordance with the invention that selectedparts of the lung ventilator unit, with the exception of insufflationhose, expiration valve, measuring probe and a number of hoses, andselected parts of the infusion unit, with the exception of cannula andhose, are combined to form a single equipment unit, that certain of saidequipment unit parts are mutually coordinated with respect tocommunication via a computer unit included in the equipment unit, andthat said computer unit is adapted to monitor unit-related criteria andpatient-related criteria.

According to proposed embodiments that lie within the scope of thepresent invention it is proposed that the computer unit is adapted todistinguish between therapeutic criteria and diagnostic criteria throughthe medium of therapeutic units and diagnostic units included in theequipment unit.

It is also proposed that one or more therapeutic units and/or one ormore diagnostic units are structured on a printed circuit board or cardand that, when applicable, function units are mounted on said board, andalso that a plurality of such boards are coordinated in the equipmentunit, and that an input of respective units is coupled internally of theequipment unit to one part of a two-part coupling device where saidparts are attached to and coordinated in the equipment unit.

The coupling parts belonging to the equipment unit are comprised of oneor more hose couplings and one or more electric connectors.

It is also proposed that an external hose part coupled to the lungventilator unit and that a number of other external hose parts arearranged in a hose bundle or hose assembly that includes a hose part forinsufflation gas, a hose part for controlling a patient-proximalexpiration valve, two hose parts for measuring pressure difference, apressure measuring hose part and/or a gas sampling hose part.

It is also proposed that the infusion unit will include a container orvessel that can be held firmly to the equipment unit but readily removedtherefrom, said container containing an anaesthesia inducingpharmaceutical in liquid phase.

It is also proposed that the coupling parts of the equipment unit shallbe connectable to a measuring probe, sensor or the like separate fromthe equipment unit, through the medium of an external hose part or anexternal electric conductor, wherewith said measuring probe, sensor orthe like may include electronic circuits adapted for sensing/detectingthe presence and the value of patient related criteria.

It is particularly proposed that a display unit is coupled to and/orsecured to said equipment unit, and that said display unit is adapted toshow the instantaneous values of one or more criteria and/or thetimewise variation of said criteria on a display surface.

With the intention of solving one or more of the aforesaid technicalproblems it is also proposed in accordance with the invention that oneor more first criteria related to one or more diagnostic units, and thatone or more second criteria related to one or more therapeutic units canbe presented on the display surface of a display unit, that one or moreof said first criteria is/are chosen for display on the display surfaceas instantaneous values, and that one or more of said first criteriais/are chosen for display on said display surface as the timewisevariation of the criterion.

By way of proposed embodiments that lie within the scope of the presentinvention it is also suggested that one or more of said second criteriais/are selected for display on the display surface as instantaneousvalues, and that one or more of said second criteria is/are selected fordisplay on said display surface as timewise variation of the criterion.

In the case of certain criteria that are selected for display as thetimewise variation of the criterion, the time axes are coordinated anddisposed in superimposed relationship.

It is necessary for sensor associated signals to be delayed in respectof some criteria.

It is also proposed that the instantaneous values of one or morecriteria related to one or more diagnostic units and/or theinstantaneous values of one or more criteria related to one or moretherapeutical units can be stored in the memory of the computer andpresented as timewise variations of the criterion, as required.

It is also proposed that a few selected instantaneous values are storedin the memory time-related for presented time curves, so that the trendtaken by the curve or certain variations in a time compressed form canbe repeated.

It is also proposed in accordance with the present invention that anequipment unit will include a lung ventilator and its associated controlunit, and an infusion unit and its associated control unit, and thatsaid equipment unit is also adapted to include and detachably hold acontainer or vessel that encloses an anaesthesia inducing pharmaceuticalin liquid phase, and that said equipment unit is also adapted to includeor to co-act with said display unit.

It is also proposed that a first coupling part of a two-part hosecoupling is attached to the equipment unit, and then particularly to oneend-wall part thereof, said coupling part being adapted for coactionwith a hose part that functions to conduct a gas flow generated in theventilator and intended for insulation.

It is also proposed that one or more first coupling parts or one or moretwo-part hose couplings is/are attached to the equipment unit, and thenparticularly to one end-wall part thereof, said coupling part beingadapted for coaction with one or more hoses for measuring pressure,measuring flow and/or analyzing gas, wherewith the equipment unit isassociated with means for evaluating different criteria, such asCO₂-content, O₂-content, breathing frequency and similar criteria.

It is also proposed that one or more first coupling parts of one or moretwo-part electric connectors is/are connected to the equipment unit,particularly to one end-wall part thereof, wherein said connector partsare adapted for coaction with one or more external electric cables thatcarry sensor-related electric signals representative of differentcriteria, such as ECG-values, SpO₂-values, BIS-values, PLET-values.

It is also proposed in accordance with the invention that there isincluded a display unit whose display surface is divided so that therecan be presented on one section of said surface one or more criteriarelating to an anaesthetised patient, where the anaesthetised state ofsaid patient has been caused by infusion of a volume of anaesthesiainducing pharmaceutical per unit of time, wherein it is particularlyproposed in accordance with the invention that a first surface area ofsaid display surface shall be adapted to display the timewise variationof a number of criteria, and that a second surface area of said displaysurface shall be adapted to display the instantaneous values of a numberof criteria.

It is also proposed in accordance with the invention that a firstsurface area of said display unit shall be adapted to display thetimewise variation of a number of criteria by arranging at least some ofthe time axes equally and in superimposed relationship.

In addition, it is proposed that a second surface area shall be dividedinto fields and that one or more criterion, suitably in an abbreviatedform, and the instantaneous value of respective criterion can bedisplayed within each field.

In the case of an arrangement that includes an equipment unit and adisplay unit it is proposed that the display unit is rotatably mountedon and readily removable from the front part of the equipment unit,above a container that encloses anaesthesia inducing pharmaceutical andthat is activatable by the control unit of the infusion unit.

It is also proposed that the control unit will include a control circuitfor regulating the volume of anaesthesia inducing pharmaceuticaladministered per unit of time that can be activated by activating means,preferably positioned adjacent to and above said container.

It is also proposed that control circuits in the control unit forregulating criteria related to the lung ventilator can be actuated viaactivating means, preferably positioned adjacent to and on one side ofsaid container.

Control circuits in a control unit for regulating a number of criteriacan also be actuated via activating means that are preferably orientatedin row within a third surface area of said display.

It is also proposed that the equipment will include activatable controlmeans adapted to hold a value of a selected criterion constant.

Advantages

Those advantages primarily afforded by an arrangement for anaesthetisinga living creature or patient by administering to the patient an infusedvolume of anaesthesia inducing pharmaceutical in liquid phase per unitof time, and while using, inter alia, a lung ventilator and an infusionunit together with associated control units, reside in the creation ofconditions which enable the requisite circuits to be combined into asingle equipment unit that can be easily transported and that requireslittle space, wherewith the requisite sensors, measuring probes, etc. tobe coupled to the equipment unit can be connected readily and positivelybetween patient and equipment unit.

The invention also includes a display unit which provides conditions formonitoring all relevant criteria in a total intravenousanaesthesia-induced state in a simple and safe fashion, so thatestablished relative criteria and their timewise variation orinstantaneous values can be overseen during surgery.

It is also possible with the aid of computer associated circuits tocreate conditions in which the evaluated measurement values are delayedso as to co-ordinate their appearance with respect to time.

The criteria-related measurement values can be held constant (closedloop) via computer related circuits, expert systems can be co-ordinatedover telecommunications networks, and conditions can be created fordistance use, relevant alarm functions can be coordinated, and differentalarm criteria can be given different priorities.

The primary characteristic features of an inventive arrangement, inaccordance with the present invention, are set forth in thecharacterizing clause of the accompanying claim 1.

The primary characteristic features of a display unit according to thepresent invention are set forth in the characterizing clause of theaccompanying claim 21.

BRIEF DESCRIPTION OF THE DRAWINGS

An earlier known arrangement and two inventive arrangements foranaesthetising a living creature or patient by administering thereto aninfused volume of anaesthesia inducing pharmaceutical in liquid phaseper unit of time will now be described in more detail with reference tothe accompanying drawings, in which

FIG. 1 lists a number of known unit-related and patient-related criteriathat can be utilised and/or evaluated beneficially with the patient inan anaesthetised state, through the medium of one or more therapeuticunits and one or more diagnostic units;

FIG. 2 is a perspective view of an earlier known system in which varioustherapeutic units and various diagnostic units are disposed in a room inmutually spaced relationship;

FIG. 3 is a block diagram illustrating a first embodiment of anintegrated equipment unit according to the invention;

FIG. 4 is a perspective external view of an equipment unit andassociated display unit included in the inventive arrangement;

FIG. 5 is a plan view of the display surface of a display unit and showsproposed orientation of first, second, third and fourth surface areassuch that timewise variation of criteria and a number of instantaneousvalues of said criteria can be monitored graphically and in a timerelationship;

FIG. 6 illustrated the principle connection of a measuring probe and avalve for enabling the flow and volume of insufflation gas andexpiration gas to be determined and controlled, and also other criteriarelated to said gas;

FIG. 7 illustrates an example of a hose bundle with a hose cross-sectionthat can be used as an integrated connection between the equipment unitand the valve/measuring probe shown in FIG. 6; and

FIG. 8 is a block diagram of a second integrated equipment unitaccording to the invention, including a number of electric circuits, alung ventilator and associated control unit, and an infusion unit andassociated control unit for regulating the supply of anaesthesiainducing pharmaceutical, and a computer unit and connected display unit.

DESCRIPTION OF KNOWN EMBODIMENTS

FIG. 1 lists a number of pieces of equipment, units andelectric/electronic circuits required to anaesthetise a living creatureor a patient by administering an infused volume of anaesthesia inducingpharmaceutical per unit of time and keeping the patient anaesthetisedduring surgery, and thereafter to arouse the patient from saidanaesthetised state.

FIG. 1 is intended to illustrate a number of therapeutic units adaptedto control the well-being of the patient, and a number of diagnosticunits adapted to sense/detect and evaluate patient-related criteria forvisually and/or audibly informing the anaesthetist and/or surgeon as tothe state of the patient, and to provide the possibility of regulatingcurrent values for each chosen criterion.

Thus, the reference A in FIG. 1 identifies a lung ventilator. Lungventilators of this particular kind are complicated and are known to theart and, in the following text, are simplified to comprise principally adrive unit 1A and a control unit 2A.

The lung ventilator A includes a first hose 3A adapted for delivery ofinsufflation gas to a patient V, and an insufflation valve 5A which isconnected to the ventilator A by the hose 3A.

The lung ventilator A also includes a second hose 4A for expiration ofgas from the patient V, and an expiration valve 6A connected to the hose4A, said second hose 4A having the same cross-section as the hose 3A.

The mutually opposite ends of the hoses 3A and 4A are combined in apatient-adapted mouthpiece.

The reference B identifies a schematically illustrated and knowninfusion unit, where movement of an infusion syringe is effected by apart 1B and a control unit 2B.

A unit B of this kind is known to the art and is based on a container inthe form of a syringe 3B that encloses an anaesthesia inducingpharmaceutical in liquid phase, and which an actuator means of astepping motor functions to press a plunger into the syringe, wherewithpharmaceutical can pass through a hose 4B so as to create infusion ofpharmaceutical into the patient's bloodstream. The control circuit 2B isdesigned to increase or decrease the volume infused per unit of time ina regulating fashion.

The distal end of the hose 4B is connected to a cannula 5B inserted inthe patient's bloodstream.

C identifies a unit which senses the air pressure prevailing in themouth and lungs of the patient, and includes an actuator part 1C and acontrol unit 2C. The instantaneous pressure in the mouth or oral cavityof the patient can be detected and determined through the medium of ahose 3C connected to the patient's mouth. This also enables thePEEP-pressure (J) to be evaluated, this pressure denoting the airpressure between insufflation phases.

D identifies a unit which includes a sensing unit 1D and a control unit2D and which functions to evaluate the flow of gas (air) into thepatient's lungs and, when necessary, the flow of expiration gas.

The unit 1D is connected to a sensor or measuring probe 5D by means oftwo hoses 3D and 4D, and the sensor or measuring probe 5D is designed toinitiate measurement of the flow, through the medium of pressuredifferences P1 and P2 in the hoses 3D and 4D. As a result oftime-related integration in the control unit 2D, the sensor or measuringprobe is also able to establish the volume during an insufflation andexpiration phase respectively in addition to establishing said flow.

The measuring probe 5D may be of the kind described and illustrated inmore detail i U.S. Pat. No. 5,088,332.

The reference letter E in FIG. 1 identifies a unit which establishes theCO₂-content and O₂-content of the insulation gas and/or the expirationgas, said unit including a sensing/detecting unit 1E and an evaluatingunit 2E. A hose 3E is connected to the unit 1E. The evaluating unit 2Eincludes circuits that enable the instantaneous value of the CO₂-contentand/or the O₂-content to be established and/or the timewise variation inthe pulsating insufflation or expiration gas.

F identifies a unit for establishing the patient's ECG-values and forevaluating the timewise variation of these values with the aid of asensing unit 1F and an evaluating unit 2F.

One or more measuring points or pads are applied to the patient andconnected by an electric conductor 3F, wherewith electric signals aredetected and evaluated partially in the unit 1F.

G identifies a blood pressure evaluating unit that includes a sensingunit 1G and an evaluating unit 2G. More particularly, the unit evaluatesan NIBP-value (Non Invasive Blood Pressure), by observing pressurevariations in the hose 3G.

H identifies a unit that evaluates blood oxygen saturation, in whichsignificant electric signals carried on a conductor 3H are received in asensing unit 1H and evaluated in an evaluating unit 2H. This value isdesignated SpO₂. The same unit can be also used to evaluate aPLET-value.

The letter I identifies the process of evaluating the degree ofconsciousness or the depth of anaesthesia of a patient through themedium of a unit that includes a receiver circuit 1I and a controlcircuit 2I and which functions to evaluate the instantaneous brainactivity of a patient.

Electric signals representing the instantaneous brain activity of thepatient arrive on the conductor 3I and are received in a circuit 1I andprocessed in the evaluating unit 2I so as to be able to show timewisevariation of the degree of consciousness and therewith enable the depthof anaesthesia of the patient to be evaluated.

The letter J identifies a device for establishing the lowest air valuein respect of lung overpressure. This value can be determined under C.

FIG. 2 is a perspective view of an earlier known array of apparatus forachieving total intravenous anaesthesia, where the individual apparatusor pieces of equipment have been combined and placed in an operatingtheatre in a co-ordinated manner.

FIG. 2 shows only some of the units and criteria shown in FIG. 1, theseunits and criteria having been given the same reference signs for thesake of illustration.

Each of the aforesaid evaluating units is designed to generate and alarmwhen the evaluated measurement value falls below or exceeds apredetermined limit of value.

DESCRIPTION OF EMBODIMENTS AT PRESENT PREFERRED

FIG. 3 is a block diagram illustrating schematically an arrangement 200constructed and integrated in accordance with the principles of theinvention, said arrangement including an equipment unit 201 (shown moreclearly in FIG. 4) which comprises mutually connected necessary piecesof equipment such as to create a mobile unit to which there is connecteda display unit 202 having a display surface according to FIG. 5.

The timewise variations of the values and the criteria to be evaluatedand presented on the display surface 202′ of the display unit 202 are inaccordance with the criteria shown in FIGS. 3, 4 and 5 (withinparenthesis);

-   (F) the timewise variation of ECG-values;-   (E) the timewise variation of the CO₂-values (or possibly the    O₂-values);-   (H) the timewise variation of the PLET-values with respect to    pulsation and strength of heart beats;-   (C) the timewise variation of the air path pressure P (or the flow    rate Q); and-   (I) the timewise variation of the depth of anaesthesia (BIS) of the    patient.    The time axes wander from left to right for all criteria.

A time axis of 20 seconds is proposed in the illustrated case. On theother hand, a time axis of about 2 hours is chosen for the BIS-curve.

The time axis of the BIS-curve can be changed so as to compress the timeaxis in respect of times that are longer than the maximum given time of2 hours, so that all measurement values will be visible during theentire operation (surgical).

With the respect to the values and criteria of instantaneous values, thedisplay surface 202′ of the display unit 202 in FIG. 5 shall be dividedso as to enable the following values to be determined from saidcriterion (in parenthesis):

-   (G) the NIBP-value (mmHG) with respect to the systolic blood    pressure, a mean value and the diastolic blood pressure;-   (F) the HR-value (BPM) denotes the heart frequency;-   (E) the EtCO₂-value denotes the CO₂-value in percentage at the end    of each expiration phase;-   (E) the RR-value (BPM) denotes the breathing frequency calculated    from the EtCO₂-value;-   (H) the SpO₂-value denotes in percentage the blood oxygen saturation    value;-   (E) the FiO₂-value denotes the fraction of inspired oxygen content    in the insufflation gas and possibly also in the expiration gas    (FeO₂);-   (D) the VL-value (liters) denotes the volume of insufflated gas and    the volume of expired gas;-   (C) the P-value (cm H₂O) denotes the pressure of the respiratory    tract and PEEP-value (J), disclosing the pressure between two    insufflation phases;-   (B) the V-inf. value (ml) denotes the volume of anaesthesia inducing    pharmaceutical delivered to the patient;-   (B) the P occl-value denotes the pressure in the container for the    infusion unit, in the form of a bar graph; and-   (I) the BIS-value denotes the depth of anaesthesia or the degree of    consciousness of the patient in percent.

In the case of the present application it is necessary to forceinsufflation gas periodically to the patient V through an insufflationhose 3A, whereas expiration gas is allowed to pass directly to thesurroundings. This can be effected through the medium of apressure-actuated valve 15. It shall be possible to move the valve 15 toa closed state via a limited overpressure on a line 7A.

Such an arrangement, without hose (4A) for the expiration gas, providesa significantly smaller compressible volume, smaller than half thevolume that needs to be actuated by the lung ventilator.

FIGS. 3 and 4 illustrate an equipment unit 201 that includes a lungventilator A and a number of requisite connection hoses, among otherthings.

As will be seen from FIG. 3, the ventilator A has an air intake and agas (O₂) intake, and the insufflation gas through the hose 3A mayconsist of pure air, pure O₂-gas or a chosen mixture thereof.

The hose 3A is thus adapted for insufflation gas and is connected to avalve 15.

The hose 3A and all other hoses and electric conductors have beenidentified with the same reference signs along their full length.

It will be noted, however, that all hoses and conductors/lines willnormally have within the equipment unit 201 an internal hose orconductor section that is connected to a two-part coupling unit in oneend-wall of the equipment unit, and will include an external hose orconductor section that is connected to a valve, measuring probe or thelike.

FIG. 3 also shows the known valve (6A in FIG. 1) divided functionally sothat a part 6A′ is included in the ventilator A and functions to applyan overpressure in the hose 7A. This overpressure can be varied betweentwo values and in accordance with the phase of the insufflation gas.

The other part is comprised of the valve 15.

The hose 7A is designed to control the valve 15 from one state toanother state with the aid of the valve 6A′ and with a controlledoverpressure, so as to force insufflation gas into the patient V in onefirst valve position and to enable expiration gas to pass freely in asecond valve position.

This free passage of the expiration gas can take place against anadapted counterpressure (the PEEP-pressure) which may range from 2–20 cmwater column for instance.

The hoses 3A and 4D are pressure-measuring hoses for measuring pressuredifferences and pressure variations generated by a gas flow.

The hose 3C is solely for measuring pressure.

The hose 3E is intended to conduct insufflation gas or expiration gas toan evaluating unit for gas analysis.

The four hoses 3C, 3E, 3D and 4D are together connected to equipment 10for sensing and evaluating the criteria C, D, E and J. The valuesobtained are sent to a computer unit 600.

The equipment intended for criteria B, F, G, H and I is also integratedin the equipment unit 201, with their respective evaluating units 2B,2F, 2G, 2H and 2I connected to the computer unit 600.

It will be evident from this that the equipment unit 201 shall haveconnected thereto seven external air or gas conducting hose parts orsections 7A, 3A, 3D, 4D, 3C, 3E and 3G, preferably of mutually differentcross-sections and/or different orientation, and also an external hose4B for conducting anaesthesia inducing pharmaceutical, and threeexternal electrical connecting lines 3F, 3H and 3I.

Also connected to the computer unit 600 is a display unit 202, whichwill be described in more detail below with reference to FIGS. 5 and 8.

FIG. 4 illustrates in perspective an inventive arrangement 200 thatincludes an equipment unit 201 and associated display unit 202, foranaesthetising a living creature by administering thereto an infusedvolume of anaesthesia-inducing pharmaceutical per unit of time with theaid, inter alia, of a lung ventilator and an infusion unit withassociated control units for regulating the magnitude of the gas volumeor the gas volume and/or the volume of pharmaceutical per unit of timeas necessary.

The complete arrangement 200 comprises and/or includes a plurality ofexternal sensors, measuring probes and the like and requisite externalhoses or conductor sections in addition to the compact equipment unit201 and associated display unit 202.

Not all of these sensors and measuring probes are shown, but merelyindicated.

An external hose section or an external electrical conductor sectionshall be capable of detachably connecting respective sensors andmeasuring probes to the equipment unit 201.

Thus, there is shown in FIGS. 3 and 4 a number of sensors which arecoordinated via an external electrical conductor section or via anindividual external hose section and each connected via an individualtwo-part coupling device to a respective connecting part in the end wall201G of the equipment unit 201. The sensor 13F is connected to theconnector part 3F′ via an external conductor section.

Pressurised air is delivered to a cuff-like sensor 13G via an externalsection of the hose 3G and the cuff squeezed or tightened so as to stopthe flow of blood. As the pressure of the air is slowly released, thepulsations occurring in the pressurised air are sensed as the blood isagain allowed to flow freely.

This section of the hose 3G between the cuff and the equipment unit 201is connected to a connector part 3G′ in the end wall 201 g via atwo-part connector.

A sensor 13H is connected to a connector 3H′ in the end wall 201 g viaan external electrical conductor section and via a two-part connector,for evaluating the S_(p)O₂-value.

A sensor 13I is connected to a connector 3I′ in the end wall 201 g via atwo-part connector and via an external electrical conductor section, forevaluating the BIS-values.

These sensors 13F, 13G, 13H and 13I may be of a known kind.

The external sections of the hoses 3A, 3C, 3D, 4D, 3E and 7A are allcoupled to a mouth-proximal valve arrangement that includes a valve 15and a measuring probe 42.

The equipment unit 201 is also designed to include and enclose essentialparts of a lung ventilating unit A whose internal hose section for theinsufflation hose 3A opens out into a two-part hose coupling that has aconnection part 3A′ in the end-wall 201 g.

Correspondingly, the internal sections of the hoses 7A, 3D, 4D, 3E and3C are adapted to open out into a respective two-part hose coupling thatincludes a connector part 7A′, 3D′, 4D′, 3E′ and 3C′ located in theend-wall 201 g.

The invention also allows all or at least selected external sections ofall hoses to the valve 15 and the measuring probe 42 to be collected ina single hose bundle 12, with a connecting part 12″ adapted for all hosesection adapted for fixed but readily removed coaction with theconnector parts 7A′, 3A′, 3D′, 4D′, 3E′ and 3C′ in the end-wall part 201g.

The equipment unit 201 is also adapted to include essential parts ofsaid infusion unit B, including the control unit 2B and the actuatorpart 1B.

The equipment unit 201 is also designed to include and detachably hold acontainer or vessel 20′ belonging to an infusion unit B and containinganaesthesia inducing pharmaceutical 22 in liquid phase, and is alsodesigned to carry said display unit 202.

As before mentioned, there extends between the valve 14 and measuringprobe 42 and the equipment unit 201 a hose bundle 12 which includes aplurality of external sections of the hoses used.

FIG. 7 shows a proposed cross-section of one such hose bundle 12, fromwhich it will be evident that solely external hose sections for hoses3A, 3D, 4D, 3C, 3E and 7A are co-ordinated in an exemplifying manner,whereas the hoses 4B and 3G have individual hose coupling 4B′, 3G′ atthe side of the hose coupling common to remaining hoses and includingthe connecting part or coupling device 12″.

As will be seen from FIG. 4, there is attached to one end-wall part 201g of the equipment unit 201 a first coupling part of the two-part hosecoupling, where it is indicated that one connecting part 3A′ is placedcentrally and where the connecting parts 7A′, 3D′, 4D′, 3E′ and 3C′ areorientated peripherally for coaction with an external hose bundle 12 ofgiven cross-section according to FIG. 7.

Anaesthesia inducing pharmaceutical is administered under an adaptedpressure via the coupling part 4B′, and the NIBP-values are sensed viathe coupling part 3G′.

Also mounted on the same end-wall part 201 g of the equipment unit 201are one or more connector parts of one or more electrical connectors,said connector parts being adapted for coaction with one or moreexternal electric cables or conductors that carry electric signalsrepresentative of different criteria, such as ECG-values (3F′),S_(p)O₂-values and PLET-values (3H′) and BIS-values 3I′ respectively.

FIG. 5 illustrates a proposed embodiment of a suitable display surface202′ in slightly larger scale than in FIG. 4.

The display unit 202 is adapted for co-operation with an arrangement ofthe kind described in the introduction and the display surface 202′functions to present one or more criteria applicable to a patient in astate of anaesthesia induced by administering to the patient a volume ofanaesthesia inducing pharmaceutical per unit of time, by infusion.

It will be seen from the figure, and also from FIG. 8, that the displaysurface 202′ is divided into a number of large and small surface areas.

A first surface area 202A is adapted to show the timewise variation of anumber of criteria, while a second surface area 202B is adapted to showthe instantaneous values of a number of criteria.

The first surface area 202A is adapted to show the timewise variation ofa chosen number of criteria, by equally orientating the time axes of anumber of criteria in mutually superimposed relationship.

More specifically, four different criteria are shown with the same timeaxes in the following order: uppermost ECG-values, followed byCO₂-values, followed by PLET-values and then the P-values.

The lowermost field shows the BIS-values with an own time axis.

The second surface area 202B is divided into fields in which a criterionis shown in each field, in an abbreviated form, with the instantaneousvalue of respective criteria shown adjacent thereto.

FIGS. 5 and 8 illustrate in all desirable clarity that an uppermostfield 81 discloses the NIBP-value and the RR-values, the next followingfield 82 discloses the EtCO₂ and RR values, the next following field 83discloses the S_(p)O₂-value and the FiO₂-value, the next following field84 discloses VL and the P-values, and that the next following field 85discloses the value Vinf concerning the volume of applied anaesthesiainducing pharmaceutical, while a field 86 shows the mean BIS-value inpercent. The display also includes a field 87 for the Poccl-value, thevalue of the pressure in container 20′.

More particularly, it is proposed in accordance with the presentinvention that one or more first criteria related to one or morediagnostic units, and one or more second criteria related to one or moretherapeutic units are allowed to be presented on a display unit or adisplay surface, that one or more of said first criteria is/are selectedfor display on said display surface as instantaneous values, and thatone or more of said first criteria is/are selected for display on saiddisplay surface as the timewise variation of the criterion.

One or more of said second criteria are chosen for display on thedisplay surface as instantaneous values, and one or more of said secondcriteria are chosen for display on said display surface as the timewisevariation of the criterion.

In the case of some criteria chosen for display as the timewisevariation of the criterion, the time axes are co-ordinated and arrangedin superimposed relationship.

In order to obtain concordance of the time axes and instantaneousvalues, it is necessary with respect to some criteria to delaysensor-related signals, for instance through the medium of time delaycircuits 2C′, 2D′, 2F′ and 2H′ with mutually adapted time delays.

It is also proposed that the instantaneous values and/or graph-relatedvalues of one or more criteria related to one or more diagnostic units,and/or corresponding values of one or more criteria related to one ormore therapeutic units are stored in the computer memory so that theinstantaneous values can be shown as timewise variation of the criterionand the graph-related values shown as compressed trends when necessary.

Referring back to FIG. 4, it will be seen that the display unit 202 isrotatably mounted on and readily removed from the front part 201 a ofthe equipment unit 201 and above a container 20′ that containsanaesthesia inducing pharmaceutical 22 and which can be actuated by thecontrol circuit of the infusion unit.

A control unit for regulating the volume of anaesthesia inducingpharmaceutical administered per unit of time can be actuated through themedium of an activating device positioned adjacent to and above thecontainer.

One or more control circuits for regulating other criteria, such ascriteria relating to the lung ventilator, can be actuated via activatingmeans positioned adjacent to and on one side of said container 20′,these activating means being referenced 210.

It is also possible within the scope of the invention to allow one ormore control circuits included in the control unit for regulating chosencriteria to be actuated through the medium of activating meansorientated in one or more rows, such as within a third surface area ofthe display unit referenced 202C in FIG. 4.

The equipment unit 201 also includes regulating means which areactivated via the computer unit and which function to regulate a valueof a chosen criterion and/or keep said value constant.

FIG. 6 shows schematically a valve arrangement 15 and an adjacentmeasuring probe 42 for controlling lung ventilation and for measuringdifferent criteria relating to the administered insufflation gas, andwhen necessary also criteria relating to the expiration gas.

FIG. 7 is a cross-sectional view of an external hose bundle 12 whose oneend is able to co-act with the equipment 12 via a coupling device 12″,while the other end of said hose bundle 12 is adapted for coaction withthe valve 15 and the measuring probe 42.

For instance, it will be seen from FIG. 7 that the hose bundle 12 has alarge hose cross-section for the connection 3A′ and the hose 3A, a hosecross-section for connection 7A′ and the hose 7A, a hose cross-sectionfor the connection 3D′ and the hose 3D, a hose cross-section for theconnection 4D′ and the hose 4D, a hose cross-section for the connection3E′ and the hose 3E, and a hose cross-section for the connection 3C′ andthe hose 3C.

FIG. 8 is a schematic block diagram showing another proposed embodimentof the mutually co-acting parts and circuits enclosed in the equipmentunit 201, wherewith certain of said parts and circuits can be controlledand monitored by a computer unit 600 that has associated programs andstorage units.

This embodiment is based on the concept of co-ordinating requisiteevaluating units included in utilised units to be included in a commoncomputer unit 600. A person skilled in this art will be able to produceon the basis of the above description software and a control systemadapted to the aforementioned functions, and it is therefore deemedunnecessary to describe the necessary programming to any greater extentin this document.

Where possible, the reference signs given in FIG. 3 have also been usedin FIG. 8 to identify corresponding function blocks.

The lung ventilator A has also been described in connection with thecircuits that require pressure and flow in order to determine desiredcriteria through the medium of said circuits. These have been shown anddescribed with reference to the lung ventilator.

It should be mentioned that the majority of the function block shown inFIG. 8 for selected criteria are known to the art, and will nottherefore be described in greater detail.

Thus, FIGS. 3 and 8 show that the occurrence/presence of and the valueof chosen criteria are delivered to a central or common computer unit600 which is connected to the display unit 202 via a line 600A which isadapted for two-way information, so that the computer unit 600 is ableto transmit desired values to the display unit 202, while the thirdsurface area 202C can be used to send instructions and messages to thecomputer unit 600 which changes the conditions of said criteria on thebasis of these signals.

It is applicable to both embodiments that structuring of theinstantaneous values presented on the display unit are field-related inthe manner shown in the enlarged view of FIG. 5.

With regard to the surface area 202C, it can be mentioned that alarmlimits can be entered and evaluated via manual actuation of the surfacesection -Alarm Limits- of the surface area 202C, that certainmeasurement values can be presented over a long time period (the timeaxis is extended) via the surface section -TRENDS-, calibration can beeffected via -CAL-, certain measurement values can be presented via-SETUP-, and the timewise variation can be frozen for closer assessmentvia -FREEZE-.

The display surface 202′ has a fourth surface area 202D in which otherrelevant information is presented, such as malfunctioning and/or analarm.

Both of the aforedescribed embodiments incorporate different time delaysfor compensation of so-called lag time.

In order to achieve timewise-correct indication of several criteria itis necessary to delay rapidly evaluatable criteria so that said criteriacan be displayed on the display at the same moment in time as criteriathat are evaluated more slowly.

For instance, it can be assumed that the CO₂-value and the O₂-value forcriterion E is the last value to appear with respect to time, andconsequently it is necessary to delay other criteria over an adaptedtime period, so that these values will appear simultaneously inco-ordination on the display surface. In practice, the delay concernedwill be shorter than one second.

Consequently, equipment corresponding to equipment 2C, 2D, 2F and 2Hinclude adapted time delay circuits 2C′, 2D′, 2F′ and 2H′, which arepreferably individually adapted.

The computer equipment 600 of both embodiments may be equipped with an-expert system-, where a utilised computer program is adapted to senseand calculate and interpret obtained measurement values and also to setalarm limits.

The computer program of the FIG. 8 embodiment is referenced 601.

A computer program 602 may be adapted to control received measurementvalues against set point values in a closed-loop-sequence.

Computer program 603 may be used to change the limit values for adaptedcriteria in accordance with the patient's weight, sex, race, etc.

The information displayed on the display surface can be transferred toanother display screen with the aid of a computer program 604 and alsowith the aid of the telecommunications network, such as over theInternet.

Although the invention has been described with reference to the use of asole infusion unit B, it will be understood that two or more such unitscan be used, with the same or mutually different pharmaceutical.

The lung ventilator A can be duplicated so that one unit is used foreach individual lung, therewith enabling separate control ofinsufflation and expiration.

It is also proposed that therapy control is effected through the mediumof keys and knobs and the equipment unit 201, while diagnostic controlcan be effected via the display unit 202.

The two illustrated and described embodiments of the invention are alsobased on the assumption that the various parts of the equipment unit aremutually co-ordinated with respect to communication via a computer unitprovided in the equipment unit, and that said computer unit is adaptedto monitor unit-related criteria and patient-related criteria.

The computer unit 600 is also adapted to distinguish between therapeuticcriteria and diagnostic criteria through the medium of therapeutic unitsand diagnostic units included in said equipment unit, said therapeuticand diagnostic units being co-arranged on a printed circuit boardincluded in the equipment unit and, when applicable, having functionunits mounted thereon, wherewith an input to respective units isconnected internally to one part of a two-part coupling device with saidpart attached to the end-wall of said equipment unit.

For instance, it can be mentioned that an ECG-board or card has aconstruction that requires three (3) connection electrodes with eachelectrode having a respective external conductor section.

The CO₂-board and O₂-board has a gas analysing unit mounted thereon.

Both boards are connected to a separately mounted sampling pump.

It will be understood that the invention is not restricted to theaforedescribed and illustrated exemplifying embodiments thereof and thatmodifications can be made within the scope of the inventive concept asillustrated in the accompanying claims.

1. An arrangement for anaesthetising a living creature and maintaining said creature anaesthetised, by administering to said creature an infused volume of an anaesthesia inducing pharmaceutical in liquid phase per unit of time, said arrangement comprising: a. at least one lung ventilator unit, an insufflation hose extending from said at least one lung ventilator unit to an expiration valve for being oriented adjacent to or mouth-proximal said creature, a measuring probe spaced from said at least one lung ventilator unit, and a plurality of further hoses extending from said at least one lung ventilator unit, b. at least one infusion unit having parts related to said infusion unit co-ordinated to said arrangement, a cannula, and a hose extending from said infusion unit and operatively connected to said cannula, c. first means related to a computer unit for monitoring unit-related criteria, d. second means related to said computer unit for monitoring creature-related criteria, e. a display unit exposing a display surface for said unit-related criteria and said creature-related criteria, f. said valve having a first part and a second part that each perform different functions, said first part being included in the at least one ventilator unit for applying an over pressure to one of said hoses, and said second part being moveable from a first valve member position to a second valve member position, so as to force insufflation gas into the creature when said second part is in said first valve member position and to enable expiration gas to pass freely from said creature when said second part in said second valve member position, g. said plurality of hoses extending from said at least one ventilator unit are adapted as pressure-measuring hoses for measuring pressure differences and pressure variations generated by a gas flow in said measuring probe adjacent said valve by using said insufflation gas flow, h. said plurality of hoses extending from said at least one ventilator unit further including a gas analysis hose operatively associated with said measuring probe and adapted to enable flow of at least one of insufflation gas and expiration gas to an evaluating unit for gas analysis, i. said gas analysis hose and said plurality of hoses extending from said at least one ventilator unit are connected to equipment for sensing and evaluating selected criteria, said selected criteria including a time wise variation of the at least one of air path pressure and a flow rate, a VL-value denoting the volume of insufflated gas and a volume valve of expired gas, and/or a FiO2 value denoting a fraction of inspired oxygen content in the insufflation gas and in the expiration gas, j. wherein a plurality of values obtained from said evaluating unit are sent to said computer unit, said plurality of values including: k. a HR value denoting a heart frequency, l. a NIBP-value denoting a systolic blood pressure, a mean value and a diastolic blood pressure, and/or m. a SpO₂ value denoting, in percentage, a blood oxygen saturation value; n. the plurality of values representing item “k” to “m” are each received by their respective control unit, and wherein each of said control units is connected to said computer unit, o. an information carrying line connecting said computer unit to said display unit, p. said information carrying line being adapted for a two-way information exchange so that the computer unit is able to transmit desired values to the display unit, q. whereby a selected surface area of said display unit can be used to send instructions and messages to said computer unit, and r. said computer unit being equipped with an expert system wherein a utilised computer program is adapted to sense and calculate and interpret obtained measurements values and set alarm limits.
 2. An arrangement according to claim 1, further comprising an equipment unit including at least said at least one ventilator unit, at least one therapeutic unit and at least one diagnostic unit, wherein at least one of said at least one therapeutic unit and said at least one diagnostic unit is structured on at least one printed circuit board, which has a function unit mounted thereon; wherein said at least one board is co-ordinated in an equipment unit, with one input of respective units connected to one part of a two-part coupling device, and wherein said part of said coupling device is attached to and co-ordinated on said equipment unit.
 3. An arrangement according to claim 2, wherein said equipment unit has connected thereto and/or affixed thereto said display unit, which is adapted for the display of at least one of instantaneous criteria value and timewise variation of the criterion on said display surface.
 4. An arrangement according to claim 1, wherein first criteria related to a diagnostic unit, and second criteria related to a therapeutic unit can be presented on a display surface of the display unit; wherein said first criteria are chosen for display on said display surface as instantaneous values; and wherein said first criteria are chosen for display on said display surface as timewise variation of the criterion.
 5. An arrangement according to claim 1, wherein time axes of selected criteria of at least one of said unit-related criteria and said creature-related criteria chosen to be shown as timewise variation of respective criteria are co-ordinated and arranged in mutually superimposed relationship.
 6. An arrangement according to claim 1, wherein signals generated by a measuring probe, a sensor in respect of chosen criteria of said unit-related criteria or said creature-related criteria are time-delayed prior to said chosen criteria being presented on the display surface.
 7. An arrangement according to claim 1, wherein instantaneous values and values concerning time related graphs for criteria related to a diagnostic unit and instantaneous value concerning time-related graphs for criteria related to a therapeutic unit can be stored in memories for presentation as timewise variation of the respective criteria.
 8. An arrangement according to claim 7, wherein the timewise variation of said respective criteria can be presented in a time compressed form.
 9. An arrangement according to claim 2, further comprising an equipment unit including at least said at least one lung ventilator unit and a plurality of said hoses, and wherein a first coupling part of a two-part hose coupling of at least one of said hoses is attached to said equipment unit, and said coupling part is adapted for a co-action with an external hose section for an insufflation gas flow and a plurality of external hose sections.
 10. An arrangement according to claim 2, wherein at least one first coupling part of said two-part coupling device is attached to the equipment unit, and wherein said at least one first coupling part is adapted for co-action with a unit for evaluating different criteria, said different criteria including CO₂-content, O₂-content, and/or breathing frequency.
 11. An arrangement according to claim 2, wherein the equipment unit has attached thereto at least one two-part electric connector, said electric connector including a first part adapted for co-action with an external electric cable that carries sensor-related electric signals representative of different criteria, said different criteria including at least ECG-values, SpO₂-values, BIS-values, and/or PLET-values.
 12. An arrangement according to claim 1, further comprising an equipment unit including at least said at least one lung ventilator unit and a plurality of said hoses, and wherein a first coupling part of a two-part hose coupling of at least one of said hoses is attached to said equipment unit, and said coupling part is adapted for a co-action with an external hose section for an insufflation gas flow and a plurality of external hose sections. 